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Question #47510
The Question
In a deep marine ecosystem, vertical stratification causes the rapid attenuation of specific light wavelengths. Regarding the vertical zonation and pigmentation of marine algae, which of the following statements is INCORRECT?
Options
- A.
Rhodophyceae thrive at great depths because their major accessory pigment, r-phycoerythrin, efficiently absorbs the highly penetrating blue-green wavelengths.
- B.
Chlorophyceae are restricted to the surface strata because the red wavelengths, which are heavily absorbed by chlorophyll a and b, are rapidly attenuated by water.
- C.
The red color of deep-water Rhodophyceae is an evolutionary adaptation to maximally absorb the long-wavelength red light that reaches the ocean floor.
- D.
Phaeophyceae occupy intermediate depths, utilizing fucoxanthin to broaden their absorption spectrum beyond what chlorophyll a and c can achieve alone.
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Correct Answer
Step-by-Step Solution
Explanation
How the Examiner Thinks
Evolutionary_Exception
Tackle problems where standard rules evolve or change based on specific environmental constraints.
Concepts Behind This Question
Chloroplast|Cyanobacteria|Svedberg_Coefficient
Why This Question Is Tricky
Common Mistakes
Conceptual Pivot: Students frequently confuse the 'reflected color' of an organism with its 'absorption spectrum'.
A common misconception is that 'Red algae need red light to survive', whereas the physical reality of deep-water attenuation dictates that they appear red precisely because they reflect the unavailable red wavelengths and absorb the abundant blue-green wavelengths.
Quick Facts About This Question
Question Information
| Subject | Biology |
| Chapter | Plant Kingdom - Class 11 |
| Concept | Algal Pigmentation Logic |
| Difficulty | 8 |
| Cognitive Load | 5 |
| Target Solve Time | 120 sec |
| Access | Free |